Forget what you thought you knew about eating fish during pregnancy.
tuna steak with veggies
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I've always felt if you wait long enough, anything you were told is unhealthy during pregnancy will eventually become healthy (with the exception of drugs and alcohol, of course). Case in point: A new study out of Spain finds eating fish, even tuna, while pregnant, may provide protective benefits for your baby, despite the fact we've been told for years to avoid it.

The study, which was published in the American Journal of Epidemiology, looked at 2,000 women's fish eating habits during pregnancy. What they found was that the women who ate more fish had kids with higher cognitive scores and fewer symptoms from the autistic spectrum.

The moms' umbilical cord blood was tested for mercury, a contaminant that has been linked to neurotoxic effects, as well as DHA, which is known to boost brain development during pregnancy. Their kids were assessed at 14 months, and then again at 5 years old.

About 600 grams of fish per week, which is about three to four servings, was associated with a 2.8 point increase in IQ scores. Eating fatty fish packed with DHA, like tuna, was especially beneficial, despite it being high in mercury. Says the study's co-author about eating fish while pregnant, "In that specific moment, a large amount of DHA is needed when the brain is growing."

Very noteworthy: Researchers did not find that higher levels of mercury in the cord blood were linked to impairment in neurodevelopment.

Currently, the FDA advises pregnant women to eat two to three servings of fish per week, but has cautioned them against consuming high-mercury fish like tuna. The authors behind this study suggest eating more fish—even fish high in mercury—does not have detrimental effects on a fetus, and is even beneficial.

So maybe my daily tuna wrap at lunch is okay? But talk about a 180! As a tuna-lover who already feels super restricted during pregnancy—no coffee! no wine! no sushi!—this study is like music to my ears! Still, I would say it's advisable not to go overboard with fish, but not to worry if you eat it often.

Melissa Willets is a writer/blogger and a mom. Follow her on Twitter (@Spitupnsuburbs), where she chronicles her love of exercising and drinking coffee, but never simultaneously.